Video encoders and decoders may be used to encode input video signals into digital data, or decode digital data into output video signals. Current video encoders may use techniques such as prediction, transform, quantization, and entropy encoding to reduce the complexity of the digital data that is being digitally encoded from input video signals. Prediction may be either intra-prediction or inter-prediction. Intra-prediction may include the use of pixels that surround a particular pixel in a frame to predict the data values of the particular pixel. In inter-prediction, the pixels in a particular frame may be predicted from pixel information in a prior frame (forward prediction), from pixel information in a subsequent frame (backward prediction), or from both the preceding frame and the subsequent frame (bi-direction prediction). Accordingly, when a block of pixel data in a frame is only predicted from other pixel values, the block may be designated as being in skip mode and no residue is signaled. Transform may make the energy of the residue (the difference between original signal and predicted signal) more concentrated. The output of the transform may be further quantized via quantization before entropy encoding is applied to the quantized values. Entropy encoding may involve a lossless data compression of the quantized values to generate the digital data that encodes the initial input video signals.
Video encoders that are used to encode input signals into digital signals may conform to various video compression standards. For example, high efficiency video coding (HEVC) is a video compression standard that may provide improved coding efficiency over previous video coding standards. The HEVC standard may include the implementation of content-adaptive binary arithmetic coding (CABAC) or content-adaptive variable length coding (CAVLC).